Krow-workspace/docs/MILESTONES/M4/planning/m4-target-schema-blueprint.md

M4 Target Schema Blueprint (Command-Ready)

Status: Draft for team alignment
Date: 2026-02-24
Owner: Technical Lead

1) Goal

Define the target database shape we want before command-backend implementation, so critical flows are atomic, secure, and scalable.

1.1 Stakeholder and tenancy model

This product should be designed as a multi-tenant platform.

1. Tenant:

• One staffing company account (example: Legendary Event Staffing and Entertainment).

2. Business:

• A customer/client account owned by a tenant.

3. User:

• A human identity (auth account) that can belong to one or more tenants.

4. Staff:

• A workforce profile linked to a user identity and tenant-scoped operations.

Practical meaning:

1. The same platform can serve multiple staffing companies safely.
2. Data isolation is by tenant_id, not only by business/vendor IDs.
3. Not every record starts as a full active user:

• invite-first or pending onboarding records are valid,
• then bound to user_id when activation is completed.

flowchart LR
  U["User identity"] --> M["Tenant membership"]
  M --> T["Tenant staffing company"]
  T --> B["Business client"]
  T --> V["Vendor partner"]
  B --> O["Orders and shifts"]
  V --> O

2) First-principles rules

1. Every critical write must be server-mediated and transactional.
2. Tenant boundaries must be explicit in data and queries.
3. Money and rates must use exact numeric types, not floating point.
4. Data needed for constraints should be relational, not hidden in JSON blobs.
5. Every high-risk state transition must be auditable and replayable.

3) Current anti-patterns we are removing

1. Direct client mutation of core entities.
2. Broad USER-auth CRUD without strict tenant scoping.
3. Financial values as Float.
4. Core workflow state embedded in generic Any/jsonb fields.
5. Missing uniqueness/index constraints on high-traffic paths.

4) Target modular schema

4.1 Identity and Access

Tables:

1. users (source identity, profile, auth linkage)
2. tenant_memberships (new; membership + base access per tenant)
3. team_members (membership + scope per team)
4. roles (new)
5. permissions (new)
6. role_bindings (new; who has which role in which scope)

Rules:

1. Unique tenant membership: (tenant_id, user_id).
2. Unique team membership: (team_id, user_id).
3. Access checks resolve through tenant membership first, then optional team/hub scope.

4.2 Organization and Tenant

Tables:

1. tenants (new canonical boundary: business/vendor ownership root)
2. businesses
3. vendors
4. teams
5. team_hubs
6. hubs

Rules:

1. Every command-critical row references tenant_id.
2. All list queries must include tenant predicate.

4.8 RBAC rollout strategy (deferred enforcement)

RBAC should be introduced in phases and not enforced everywhere immediately.

Phase A: Auth-first (now)

1. Require valid auth token.
2. Resolve tenant context.
3. Allow current work to continue while logging actor + tenant + action.

Phase B: Shadow RBAC

1. Evaluate permissions (allow/deny) in backend.
2. Log decisions but do not block most requests yet.
3. Start with warnings and dashboards for denied actions.

Phase C: Enforced RBAC on command writes

1. Enforce RBAC on /commands/* only.
2. Keep low-risk read flows in transition mode.

Phase D: Enforced RBAC on high-risk reads

1. Enforce tenant and role checks on sensitive read connectors.
2. Remove remaining broad user-level access.

flowchart LR
  A["Auth only"] --> B["Shadow RBAC logging"]
  B --> C["Enforce RBAC on command writes"]
  C --> D["Enforce RBAC on sensitive reads"]

4.3 Scheduling and Orders

Tables:

1. orders
2. order_schedule_rules (new; replaces schedule JSON fields)
3. shifts
4. shift_roles
5. shift_role_requirements (optional extension for policy rules)
6. shift_managers (new; replaces managers: [Any!])

Rules:

1. No denormalized assignedStaff or shifts JSON in orders.
2. Time constraints: start_time < end_time.
3. Capacity constraints: assigned <= count, filled <= workers_needed.
4. Canonical status names (single spelling across schema).

4.4 Staffing and Matching

Tables:

1. staffs
2. staff_roles
3. workforce
4. applications
5. assignments

Rules:

1. One active workforce relation per (vendor_id, staff_id).
2. One application per (shift_id, role_id, staff_id) unless versioned intentionally.
3. Assignment state transitions only through command APIs.

4.5 Compliance and Verification

Tables:

1. documents
2. staff_documents
3. certificates
4. verification_jobs
5. verification_reviews
6. verification_events

Rules:

1. Verification is asynchronous and append-only for events.
2. Manual review is explicit and tracked.
3. Government ID and certification provider references are persisted.

4.6 Financial and Payout

Tables:

1. invoices
2. invoice_templates
3. recent_payments
4. accounts (refactor to tokenized provider references)

Rules:

1. Replace monetary Float with exact numeric (DECIMAL(12,2) or integer cents).
2. Do not expose raw account/routing values in query connectors.
3. Add one-primary-account constraint per owner.

4.7 Audit and Reliability

Tables:

1. domain_events (new)
2. idempotency_keys (already started in command API SQL)
3. activity_logs

Rules:

1. Every command write emits a domain event.
2. Idempotency scope: (actor_uid, route, idempotency_key).

5) Target core model (conceptual)

erDiagram
  TENANT ||--o{ BUSINESS : owns
  TENANT ||--o{ VENDOR : owns
  TENANT ||--o{ TEAM : owns
  TEAM ||--o{ TEAM_MEMBER : has
  USER ||--o{ TEAM_MEMBER : belongs_to

  BUSINESS ||--o{ ORDER : requests
  VENDOR ||--o{ ORDER : fulfills
  ORDER ||--o{ ORDER_SCHEDULE_RULE : has
  ORDER ||--o{ SHIFT : expands_to
  SHIFT ||--o{ SHIFT_ROLE : requires
  SHIFT ||--o{ SHIFT_MANAGER : has

  USER ||--o{ STAFF : identity
  STAFF ||--o{ STAFF_ROLE : skills
  VENDOR ||--o{ WORKFORCE : contracts
  STAFF ||--o{ WORKFORCE : linked
  SHIFT_ROLE ||--o{ APPLICATION : receives
  STAFF ||--o{ APPLICATION : applies
  SHIFT_ROLE ||--o{ ASSIGNMENT : allocates
  WORKFORCE ||--o{ ASSIGNMENT : executes

  STAFF ||--o{ CERTIFICATE : has
  STAFF ||--o{ STAFF_DOCUMENT : uploads
  DOCUMENT ||--o{ STAFF_DOCUMENT : references
  STAFF ||--o{ VERIFICATION_JOB : subject
  VERIFICATION_JOB ||--o{ VERIFICATION_REVIEW : reviewed_by
  VERIFICATION_JOB ||--o{ VERIFICATION_EVENT : logs

  ORDER ||--o{ INVOICE : billed_by
  INVOICE ||--o{ RECENT_PAYMENT : settles
  TENANT ||--o{ ACCOUNT_TOKEN_REF : payout_method

  ORDER ||--o{ DOMAIN_EVENT : emits
  SHIFT ||--o{ DOMAIN_EVENT : emits
  ASSIGNMENT ||--o{ DOMAIN_EVENT : emits

6) Command write boundary on this schema

flowchart LR
  A["Frontend app"] --> B["Command API"]
  B --> C["Policy + validation"]
  C --> D["Single database transaction"]
  D --> E["orders, shifts, shift_roles, applications, assignments"]
  D --> F["domain_events + idempotency_keys"]
  E --> G["Read models and reports"]

7) Minimum constraints and indexes to add before command build

7.1 Constraints

1. shift_roles: check assigned >= 0 AND assigned <= count.
2. shifts: check start_time < end_time.
3. applications: unique (shift_id, role_id, staff_id).
4. workforce: unique active (vendor_id, staff_id).
5. team_members: unique (team_id, user_id).
6. accounts (or token ref table): unique primary per owner.

7.2 Indexes

1. orders (tenant_id, status, date).
2. shifts (order_id, date, status).
3. shift_roles (shift_id, role_id, start_time).
4. applications (shift_id, role_id, status, created_at).
5. assignments (workforce_id, shift_id, role_id, status).
6. verification_jobs (subject_id, type, status, created_at).
7. invoices (business_id, vendor_id, status, due_date).

8) Data type normalization

1. Monetary: Float -> DECIMAL(12,2) (or integer cents).
2. Generic JSON fields in core scheduling: split into relational tables.
3. Timestamps: store UTC and enforce server-generated creation/update fields.

9) Security boundary in schema/connectors

1. Remove broad list queries for sensitive entities unless tenant-scoped.
2. Strip sensitive fields from connector query payloads (bank/routing).
3. Keep high-risk mutations behind command API; Data Connect remains read-first for client.

10) Migration phases (schema-first)

flowchart TD
  P0["Phase 0: Safety patch
  - lock sensitive fields
  - enforce tenant-scoped queries
  - freeze new direct write connectors"] --> P1["Phase 1: Core constraints
  - add unique/check constraints
  - add indexes
  - normalize money types"]
  P1 --> P2["Phase 2: Tenant and RBAC base tables
  - add tenants and tenant_memberships
  - add roles permissions role_bindings
  - run RBAC in shadow mode"]
  P2 --> P3["Phase 3: Scheduling normalization
  - remove order JSON workflow fields
  - add order_schedule_rules and shift_managers"]
  P3 --> P4["Phase 4: Command rollout
  - command writes on hardened schema
  - emit domain events + idempotency
  - enforce RBAC for command routes"]
  P4 --> P5["Phase 5: Read migration + cleanup
  - migrate frontend reads as needed
  - enforce RBAC for sensitive reads
  - retire deprecated connectors"]

11) Definition of ready for command backend

1. P0 and P1 complete in dev.
2. Tenant scoping verified in connector tests.
3. Sensitive field exposure removed.
4. Core transaction invariants enforced by schema constraints.
5. Command API contracts mapped to new normalized tables.
6. RBAC is in shadow mode with decision logs in place (not hard-blocking yet).

12) Full current model relationship map (all models)

flowchart LR
  Account["Account"]
  ActivityLog["ActivityLog"]
  Application["Application"]
  Assignment["Assignment"]
  AttireOption["AttireOption"]
  BenefitsData["BenefitsData"]
  Business["Business"]
  Category["Category"]
  Certificate["Certificate"]
  ClientFeedback["ClientFeedback"]
  Conversation["Conversation"]
  Course["Course"]
  CustomRateCard["CustomRateCard"]
  Document["Document"]
  EmergencyContact["EmergencyContact"]
  FaqData["FaqData"]
  Hub["Hub"]
  Invoice["Invoice"]
  InvoiceTemplate["InvoiceTemplate"]
  Level["Level"]
  MemberTask["MemberTask"]
  Message["Message"]
  Order["Order"]
  RecentPayment["RecentPayment"]
  Role["Role"]
  RoleCategory["RoleCategory"]
  Shift["Shift"]
  ShiftRole["ShiftRole"]
  Staff["Staff"]
  StaffAvailability["StaffAvailability"]
  StaffAvailabilityStats["StaffAvailabilityStats"]
  StaffCourse["StaffCourse"]
  StaffDocument["StaffDocument"]
  StaffRole["StaffRole"]
  Task["Task"]
  TaskComment["TaskComment"]
  TaxForm["TaxForm"]
  Team["Team"]
  TeamHub["TeamHub"]
  TeamHudDepartment["TeamHudDepartment"]
  TeamMember["TeamMember"]
  User["User"]
  UserConversation["UserConversation"]
  Vendor["Vendor"]
  VendorBenefitPlan["VendorBenefitPlan"]
  VendorRate["VendorRate"]
  Workforce["Workforce"]

  Application --> Shift
  Application --> ShiftRole
  Application --> Staff
  Assignment --> ShiftRole
  Assignment --> Workforce
  BenefitsData --> Staff
  BenefitsData --> VendorBenefitPlan
  Certificate --> Staff
  ClientFeedback --> Business
  ClientFeedback --> Vendor
  Course --> Category
  Invoice --> Business
  Invoice --> Order
  Invoice --> Vendor
  InvoiceTemplate --> Business
  InvoiceTemplate --> Order
  InvoiceTemplate --> Vendor
  MemberTask --> Task
  MemberTask --> TeamMember
  Message --> User
  Order --> Business
  Order --> TeamHub
  Order --> Vendor
  RecentPayment --> Application
  RecentPayment --> Invoice
  Shift --> Order
  ShiftRole --> Role
  ShiftRole --> Shift
  StaffAvailability --> Staff
  StaffAvailabilityStats --> Staff
  StaffDocument --> Document
  StaffRole --> Role
  StaffRole --> Staff
  TaskComment --> TeamMember
  TeamHub --> Team
  TeamHudDepartment --> TeamHub
  TeamMember --> Team
  TeamMember --> TeamHub
  TeamMember --> User
  UserConversation --> Conversation
  UserConversation --> User
  VendorBenefitPlan --> Vendor
  VendorRate --> Vendor
  Workforce --> Staff
  Workforce --> Vendor